The present invention relates generally to integrated circuits, and more particularly to an integrated circuit system for processing and displaying video and graphics.
Video and graphics systems are typically used in television control electronics, such as set top boxes, integrated digital TVs, and home network computers. Video and graphics systems may receive and process compressed data streams, an example of which is an MPEG-2 Transport stream. Video and graphics systems used to process compressed data streams may include a data transport processor for extracting message data and other information from the compressed data streams.
This application includes references to both graphics and video, which reflects in certain ways the structure of the hardware itself. This split does not, however, imply the existence of any fundamental difference between graphics and video, and in fact much of the functionality is common to both. Graphics as used herein may include graphics, text and video.
One embodiment of the present invention is a transport processor for receiving and processing compressed data streams. The transport processor includes a descrambler for decrypting one or more compressed data streams when the one or more compressed data streams have been encrypted, and a PCR recovery module for extracting PCRs contained in the compressed data streams and for providing the extracted PCRs as an output. The PCR recovery module has a direct load capability for receiving user defined PCRs and outputting them instead of outputting the extracted PCRs. The compressed data streams may have been encrypted using either DES or DVB encryption method. The PCR recovery module may be capable of extracting PCRs from both MPEG Transport streams and DIRECTV transport streams.
Another embodiment of the present invention is a method of receiving and processing compressed data streams. The method includes decrypting one or more compressed data streams when the one or more compressed data streams have been encrypted, extracting PCRs contained in the compressed data streams, and providing the extracted PCRs as an output.
Yet another embodiment of the present invention is a transport processor including a transport recorder for storing portions of compressed data streams in memory and a playback circuit for reading the stored portions of the compressed data streams. The playback circuit includes a throttling mechanism and a hold mechanism to prevent overflow in video and audio buffers.
Yet another embodiment of the present invention is a video and graphics system. The system includes an input for receiving analog video data, an input for receiving graphics data, a core transport processor for receiving and processing a plurality of compressed data streams, a first satellite transport processor for receiving at least one of the compressed data streams and extracting video data, and a second satellite transport processor for receiving at least one of the compressed data streams and extracting audio data. The core transport processor uses a clock reference recovery module to extract clock reference data from the compressed data streams, and provide the extracted clock reference data to downstream devices including at least one of the first satellite transport processor and the second satellite transport processor. The video and graphics system may be implemented on an integrated circuit chip.